Assuming you are talking about your Wireless and networks list...my guess would be that the DreyTek device you are seeing is a DreyTek router that is close enough to show on your list. As to whether you are being hacked by the device is hard to say..but since it disappears and reappears would suggest a drop in signal strength or the individual physically turning off the device. If you are that concerned I'd look into getting some heavy duty anti virus software that includes antiphishing, etc. box stores/tech stores should be able to help with that.
At home we have two laptops, a mediaserver and a router, together forming our home network. The mediaserver is supplied by the cable company and serves our TV set. All use WPA/WPA2 personal passwords to connect and I have not used simple codes. Since about two weeks there seems to be an intruder in my network. In the explorer, under "Network" I see every now and then a second router called DrayTekAPs. When I open my own router and look at the list of devices connected, The DrayTek is NOT there. It seems to connect to our laptops, not to our router. Since there are many routers in the neighborhood, I have searched for one that uses the name DrayTekAPs, but there is none. It maybe there but not show its SSID.(?)
I have checked the properties of all our own equipment, but none has a wireless card made by Draytek on board. Also, when I open "properties" of this intruding DrayTek device, it shows little information and a serial number 123456789, which makes me rather suspicious. Often the device disappears shortly after having been approached this way. I cannot remove or disable it.
I am worried somebody has hacked my network and is stealing information or is there a simple technical explanation for this?

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